Recording and/or reproducing device for magnetic tape

ABSTRACT

A recording and/or reproducing apparatus for a magnetic tape includes a supply side reel gear, a takeup side reel gear, a tape guide drum about which the magnetic tape pulled out from a tape cassette is wound, a tape loading mechanism for pulling out the magnetic tape from the tape cassette and for placing it on the tape guide drum by way of tape loading and for housing it in the tape cassette by way of tape unloading, and a switching mechanism for switching the running direction of the magnetic tape pulled out from the tape cassette. This switching mechanism includes a counter gear positioned between the supply side reel gear and the takeup side reel gear during loading of the magnetic tape by the tape loading mechanism, and controls the running direction of the magnetic tape by the counter gear selectively meshing with the supply side reel gear or the takeup side reel gear after completion of the loading of the magnetic tape. Since the running direction of the magnetic tape is controlled by switching of the counter gear, the running direction of the magnetic tape can be switched promptly.

TECHNICAL FIELD

This invention relates to a recording and/or reproducing apparatusemploying a magnetic tape as a recording medium. More particularly, itrelates to a recording and/or reproducing apparatus having a tapeloading mechanism for pulling out a magnetic tape housed in a tapecassette loaded on a cassette loading mechanism within a main body unitof the apparatus by a tape loading mechanism for loading the tape on apre-set tape running route.

BACKGROUND ART

A recording and/or reproducing apparatus employing a tape cassettehousing a magnetic tape as a recording medium is currently in use. Asthis sort of the recording and/or reproducing apparatus, there is knownan audio PCM tape recorder or a video tape recorder having a rotarymagnetic head device which is comprised of a rotary magnetic head havingsliding contact with the magnetic tape pulled out of the tape cassette,or a tape guide drive.

In this recording and/or reproducing apparatus, information signals arerecorded and/or reproduced for a magnetic tape by causing the rotarymagnetic head to have a sliding contact with the magnetic tape run fromor to a tape guide drum.

The recording and/or reproducing apparatus having the rotary magnetichead device is provided with a tape loading mechanism for pulling outthe magnetic tape housed in the tape cassette for being taken up on atape guide drum after running on a pre-set tape running path in the mainbody unit of the apparatus. The tape loading mechanism has a movementguide block which is moved between the tape cassette loading mechanismand the rotary magnetic head device. This movement guide block has aguide roll about which the magnetic tape is hooked so as to be pulledout of the tape cassette and so as to be automatically loaded on thetape running route. The magnetic tape wound about the tape guide drum isrun at a constant velocity as it is clinched between a capstan arbor runin rotation by a capstan motor and a pinch roll.

Meanwhile, in a recording and/or reproducing apparatus, such as an audioPCM tape recorder having a rotary magnetic head device, there areoccasions wherein the magnetic tape is run in a direction reversed forthe forward direction for recording and/or reproducing informationsignals for the magnetic tape as when retrieving the signals recorded onthe magnetic tape or re-writing sub-codes.

For doing these operations, this sort of the tape recorder includes amechanism for selectively driving supply side or take-up side reelshafts depending on the tape running direction. The mechanism forswitching between the reel shafts to be in operation depending on thetape running direction is adapted for transmitting the driving force ofthe reel shaft driving motor to one of the reel shafts, and is providedindependently of the capstan motor adapted for running the magnetic tapeat a constant velocity.

With the recording and/or reproducing apparatus having the capstan motorfor running the magnetic tape at a constant velocity and the drivingmotor for driving the reel shaft, the capstan motor and the reel shaftdriving motor can be controlled independently of each other, and hencethe magnetic tape can be taken up simultaneously with switching of therunning direction of the magnetic tape, thus assuring prompt switchingof the tape running direction.

With this sort of the recording and/or reproducing apparatus, thefollowing inconvenience arises when accommodating the magnetic tapepulled out on the tape running route in the tape cassette by way ofunloading for taking out the tape cassette from the cassette loadingunit in the main body unit of the apparatus.

For loading the magnetic tape on a pre-set tape running route, themagnetic tape is pulled out of the tape cassette. It is thereforenecessary for the driving force transmitting gear transmitting thedriving force of the reel shaft driving motor to the supply side reelshaft not to mesh with the supply side reel shaft. For unloading themagnetic tape, it is necessary for the driving power transmitting gearto be engaged with the supply side reel shaft.

Since the driving power transmitting gear is engaged with the reel shaftwhen the tape cassette is ejected from the cassette loading unit in themain body unit, it is necessary to separate the driving powertransmitting gear meshing with the supply side reel shaft from the reelshaft when loading the tape cassette on the cassette loading unit forloading the magnetic tape on the pre-set tape running route. With thissort of the recording and/or reproducing apparatus, such a mechanism isrequired which is adapted for spacing the driving power transmittinggear from the reel shaft for loading the magnetic tape from the unloadedstate, thus complicating the structure of the tape loading mechanism.

Moreover, if a large amount of the magnetic tape is wound on a tapereel, the winding diameter is increased, thus raising the tape take-upspeed. Conversely, if a small amount of the magnetic tape is wound on atape reel, the winding diameter is decreased, thus lowering the tapetake-up speed. Thus, it may be feared that, depending on the windingstate of the magnetic tape on the tape reel, the speed with which themagnetic tape is taken up on the tape reel becomes faster than the speedwith which the movable guide block constituting the tape loadingmechanism of the magnetic recording and/or reproducing apparatus ismoved from the loading position laterally of the rotary magnetic headdevice to the tape cassette loading position, thus possibly imposingtension larger than is necessary on the magnetic tape to destroy thetape.

On the other hand, the recording and/or reproducing apparatus, employingthe tape cassette as a recording medium and which is provided with arotary magnetic head device, includes a tape cassette transfer member ora cassette holder supported for movement across the tape cassetteloading/unloading position and the tape cassette loading position. Thetape cassette is moved via the tape cassette transfer member or thecassette holder to the tape cassette loading position so as to be loadedon the cassette loading unit of the main body portion of the recordingand/or reproducing apparatus.

The magnetic tape pulled out of the tape cassette is wound about thetape guide drum a pre-set angular extent to achieve sliding contact withthe rotary magnetic head. Thus, the running route of the magnetic tapeis of a complex shape, being of a substantially M- or U-shape about therotary magnetic head as center. The recording and/or reproducingapparatus has the above-mentioned tape loading mechanism for loading themagnetic tape on this complex tape running route.

Meanwhile, in a recording and/or reproducing apparatus, reduced to aportable size, the apparatus in its entirety is small-sized, so thatcomponent parts of the tape loading mechanism are spaced apart from oneanother an extremely small distance, that is, these component parts areproximate to one another. Thus, the movable guide block, constitutingthe tape loading mechanism, is located extremely close to the rotarymagnetic head device when the guide block is moved to close to themagnetic head device. Also, the movable guide block is mechanicallysupported by a supporting arm supporting it, so that, by the supportingarm making its rotation, the movable guide block is moved between thetape cassette loading position and the rotary magnetic head position.Since the movable guide block is mechanically supported as describedabove, it has some allowance, so that, if it is moved to close to therotary magnetic head device, the risk is high that the guide block istilted towards and occasionally contacted with the rotary magnetic head.

If the magnetic tape recording and/or reproducing apparatus, having theabove-mentioned rotary magnetic head device, is in therecording/reproducing mode of recording/reproducing information signals,the pinch rolls are pressed against a capstan, and hence the magnetictape is clinched therebetween and run at a constant velocity. If theapparatus is in the fast-feed mode, the pinch roll is spaced apart fromthe capstan, while the supply side reel, operating as the tape supplyside, is set so as to be rotatable freely. The take-up side reel isrotated at a high velocity by a reel driving motor for running themagnetic tape at an elevated speed in order to take up the tape on thetake-up side reel. If the apparatus is in the rewind mode, that is in amode of rewinding the magnetic tape once taken up on the take-up roll,the pinch roll is spaced apart from the capstan, while the take-up sidereel, operating as the tape supply side, is set so as to be rotatablefreely. The supply side reel is rotated at a high velocity by the reeldriving motor for running the magnetic tape at an elevated speed inorder to rewind the tape on the supply side reel.

Meanwhile, if, in the recording/reproducing apparatus having theconventional rotary magnetic head device, the running of the magnetictape is to be halted during fast feed or rewind operations, the drivingcurrent to the reel driving motor is turned off, at the same time as abraking unit, such as a braking pad, is applied against a portion of amechanism for transmitting the driving power of the driving motor to thereel, in order to prevent the take-up side reel or the supply side reelfrom being rotated by the force of inertia of the driving motornotwithstanding the interruption of the driving current.

There is also such a recording/reproducing apparatus in which, insteadof providing a forced braking mechanism, such as brake pad, the brakingcurrent opposite in direction to that of the driving current during thefast feed mode or rewind mode is supplied to the reel driving motor forapplying an abrupt braking action to the reel driving motor.

If a large amount of the magnetic tape is wound on the tape reel set toa rotatable state, the tape reel keeps on to be rotated by its force ofinertia to reel out the magnetic tape, no matter whether the rotation ofthe reel driving motor is halted by the above-mentioned brakingmechanism or by the control current. The result is that the magnetictape is slackened on cessation of the fast feed or rewind operations.

In the magnetic tape recording and/or reproducing apparatus adapted forhalting rotation of the reel driving motor by the control current, itmay be contemplated to decrease the control current gradually to preventthe magnetic tape from being slackened, that is to lower the voltage ofthe braking current applied to the coil of the reel driving motor, forgradually braking the reel driving motor. However, with the reel drivingmotor, the braking applied to the driving motor is strong so that themagnetic tape cannot be prevented from becoming slackened even if thevoltage of the braking current is lowered gradually.

DISCLOSURE OF THE INVENTION

It is therefore an object of the present invention to provide a novelrecording and/or reproducing apparatus for a magnetic tape whereby theabove-mentioned problems inherent in the conventional magnetic taperecording and/or reproducing apparatus can be resolved.

It is another object of the present invention to provide a recordingand/or reproducing apparatus for a magnetic tape whereby the magnetictape is prevented from being destroyed to assure positive protection ofthe magnetic tape in order to realize tape loading.

It is a further object of the present invention to provide a recordingand/or reproducing apparatus for a magnetic tape whereby the apparatusin its entirety can be reduced in size in order to simplify thestructure for switching the operational modes.

It is a further object of the present invention to provide a recordingand/or reproducing apparatus for a magnetic tape whereby the tapeloading mechanism for pulling out the magnetic tape from the tapecassette loaded on the main body unit for loading on a pre-set taperunning route can be reduced in size to reduce the size of the entireapparatus.

It is a further object of the present invention to provide a recordingand/or reproducing apparatus for a magnetic tape whereby the magnetictape can be prevented from being damaged and can be loaded or unloadedreliably in safety.

It is a further object of the present invention to provide a recordingand/or reproducing apparatus for a magnetic tape whereby it is possibleto prevent the rotary magnetic head device from being partiallycontacted with a portion of the tape loading mechanism during tapeloading/unloading to prevent resulting destruction of the tape loadingmechanism and/or the rotary magnetic head device.

It is yet another object of the present invention to provide a recordingand/or reproducing apparatus for a magnetic tape whereby the magnetictape can be taken up in trim state on the tape reel without slack on theoccasion of fast feed or rewind of the magnetic tape.

For accomplishing the above objects, the present invention provides arecording and/or reproducing apparatus for a magnetic tape including asupply side reel for reeling out a magnetic tape, a supply side reelgear for rotationally driving the supply side reel, a takeup side reelfor taking up the magnetic tape, a tape guide drum about which themagnetic tape pulled out from the tape cassette is wound, a takeup sidereel gear for rotationally driving the takeup side reel, a tape loadingmechanism for pulling out the magnetic tape from the tape cassette forplacing it on the tape guide drum by way of tape loading and forseparating the magnetic tape away from the tape guide drum for housingit in the tape cassette by way of tape unloading and a switchingmechanism for switching the running direction of the magnetic tapepulled out from the tape cassette by the tape loading mechanism.

The switching mechanism has a counter gear movable between a position inwhich the counter gear selectively meshes with the supply side reel gearor the takeup side reel gear for selectively driving one of the supplyside reel gear and the takeup side reel gear and a position in which thecounter gear is positioned between the supply side reel gear and thetakeup side reel gear and is spaced apart from one of the supply sidereel gear and the takeup side reel gear. The counter gear is positionedduring the magnetic tape loading operation by the tape loading mechanismbetween the supply side reel gear and the takeup side reel gear.

After the end of the unloading operation by the tape loading mechanism,the counter gear is moved to a position which is intermediate betweenthe supply side reel gear and the takeup side reel gear and which isspaced apart from one of the supply side reel gear and the takeup sidereel gear.

The tape loading mechanism includes a pair of movement guides movablebetween a position of pulling out the magnetic tape from the tapecassette and a position of wrapping the magnetic tape pulled out fromthe tape cassette about the tape guide drum, and a movement guidemechanism for moving the movable guides. There is further provided adriving mechanism for driving the movement mechanism of the tape loadingmechanism.

The movement mechanism has a cam gear having a cam portion for drivingthe movement mechanism and a slider moved by the cam gear for drivingthe movement mechanism.

The recording and/or reproducing apparatus according to the presentinvention further includes an operating mechanism for tilting one of thepaired movement guides in a direction away from the tape guide drum whenthe paired movement guides are moved to a position proximate to the tapeguide drum.

The recording and/or reproducing apparatus for the magnetic tapeaccording to the present invention further includes supporting means forrotatably supporting the tape guide drum. An operating mechanism isprovided on the supporting means.

The operating mechanism is a lug provided on the supporting means andwhich is abutted against the one movement guide for tilting the movementguide.

The recording and/or reproducing apparatus for the magnetic tape furtherincludes a switching mechanism moved by the driving mechanism forselectively engaging the counter gear with one of the supply side reelgear and the takeup side reel gear.

The driving mechanism includes a cam gear having a cam portion fordriving the switching mechanism and a slider moved by the cam gear fordriving the switching mechanism.

The recording and/or reproducing apparatus for a magnetic tape includesa tape guide drum about which is wound the magnetic tape pulled out of atape cassette, a tape pull-out mechanism having a pair of movementguides movable between a position of pulling out the magnetic tape fromthe tape cassette and a position of wrapping the magnetic tape pulledout from the tape cassette about the tape guide drum, and an operatingmechanism for tilting one of the paired movement guides in a directionaway from the tape guide drum when the paired movement guides have beenmoved to a position proximate to the tape guide drum.

The present invention also provides a recording and/or reproducingapparatus for a magnetic tape including a supply side reel for feedingout the magnetic tape, a takeup side reel for taking up the magnetictape, rotation detection means for detecting rotation of the supply sidereel and of the takeup side reel, and a running mechanism for runningthe magnetic tape at a constant speed. The running mechanism has acapstan and a capstan motor for rotationally driving the capstan and isadapted for running the magnetic tape at a constant speed. There is alsoprovided control means for controlling the capstan motor based onresults of detection from the detection means. The control meanssupplies a control signal to the capstan motor until the period of adetection signal from the detection means reaches a pre-set period sothat the capstan motor is rotated in reverse when the running speed ofthe magnetic tape is slowed by the running mechanism.

The control means halts the supply of the control signal to the capstanmotor when the period of the detection signal from the detection meansis not less than the pre-set period.

The control means generates the duty of the control signal based on theresults of detection of the supply side reel by the detection means androutes the generated duty to the capstan motor.

The control means calculates the amount of the magnetic tape wound aboutthe supply side reel based on the results of detection by the detectionmeans and generates the control signal based on the calculated results.

The present invention also provides a recording and/or reproducingapparatus for a magnetic tape including a supply side reel for feedingout the magnetic tape, a takeup side reel for taking up the magnetictape, rotation detection means for detecting rotation of the supply sidereel and of the takeup side reel, and a running mechanism for runningthe magnetic tape at a constant speed. The running mechanism has acapstan and a capstan motor for rotationally driving the capstan andbeing adapted for running the magnetic tape at a constant speed. Thereis provided control means for controlling the capstan motor based onresults of detection from the detection means. The control means sendsthe control signal to the capstan motor until detection of cessation ofrotation of the supply side reel and/or rotation of the takeup side reelon detection of tape end.

Other objects and illustrative advantages of the present invention willbecome apparent from the description of the preferred embodiments of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view, looking from the upper surface side,showing a tape cassette used in a tape recorder equipped with a rotarymagnetic head device of the present invention.

FIG. 2 is a perspective view showing the tape cassette, looking from thelower surface side.

FIG. 3 is a perspective view, looking from the lower surface side,showing the tape cassette with the front lid opened.

FIG. 4 is a plan view showing the mechanical portion of the taperecorder provided with the rotary magnetic head device according to thepresent invention.

FIG. 5 is a plan view showing the magnetic tape pulled out to the taperunning route and wound on the tape guide drum.

FIG. 6 is a plan view showing a driving power transmission unit fortransmitting the driving power of the driving power to a reel shaftgear.

FIG. 7 is a plan view showing a third connection arm portion rotated bya movement actuation unit of the movable guide block.

FIG. 8 is a cross-sectional view showing a clutch gear mounted on arotary base block.

FIG. 9 is a plan view of a reel shaft selection unit showing themagnetic tape being pulled out from the tape cassette.

FIG. 10 is a plan view of the reel shaft selection unit showing themagnetic tape being completely pulled out from the tape cassette.

FIG. 11 is a plan view of the reel shaft selection unit showing themagnetic tape run at a constant velocity in the forward direction afterbeing pulled out to the tape running route and wound about the rotarymagnetic head device.

FIG. 12 is a plan view of the reel shaft selection unit showing themagnetic tape being run in the reverse direction.

FIG. 13 is a plan view of the reel shaft selection unit showing themagnetic tape pulled out to the tape running route and taken up on thetape cassette.

FIG. 14 is a plan view of the rotary magnetic head type tape recorderprovided with a tape tension according unit adapted for according backtension to the running magnetic tape.

FIG. 15 is a cross-sectional of a tension according unit adapted foraccording back tension to the running magnetic tape.

FIG. 16 is a side view of the rotary magnetic head device and first andsecond movable guide blocks.

FIG. 17 is a plan view of the rotary magnetic head device and first andsecond movable guide blocks.

FIG. 18 is a side view showing the second movable guide block tilted inone direction.

FIG. 19 is a side view showing the second movable guide block tilted inthe other direction.

FIG. 20 is a cross-sectional side view showing a modification of themechanism for tilting the second movable guide block.

FIG. 21 is a block diagram showing a recording/reproducing system of thetape recorder according to the present invention.

FIG. 22 is a perspective view showing a main mechanical portion forrunning the magnetic tape.

FIG. 23 is a waveform diagram showing a control PWM signal sent to acapstan motor used for running the magnetic tape.

BEST MODE FOR CARRYING OUT THE INVENTION

In the following, a recording and/or reproducing apparatus for amagnetic tape according to the present invention, as applied to a taperecorder of the rotary magnetic head system, reduced to a portable size,is explained.

A tape cassette 1, used for a tape recorder of the rotary magnetic headsystem, embodying the present invention, is explained with reference toFIGS. 1 to 3.

The tape cassette 1 includes a main body unit of the cassette 4 made upof paired upper and lower cassette halves 2, 3, abutted and joinedtogether, as shown in FIG. 1. The main body unit of the cassette 4 haspaired tape reels 5, 6 mounted rotatably therein and holds a magnetictape 7 placed on these tape reels. The magnetic tape 7, extended tooutside the front surface of the main body unit of the cassette 4 viatape pull-out ports 8, 9 formed on both ends in the front side of themain body unit of the cassette 4, is placed across the tape reel 5 andthe opposite side tape reel 6. On the front side of the main body unitof the cassette 4 is rotatably mounted a front lid 11 adapted forprotecting the magnetic tape 7, extended on the front surface side ofthe main body unit of the cassette 4, during non-loading time of thetape cassette 1 on the tape recorder. The front lid 11 is rotationallybiased in a direction of closing the magnetic tape 7, extended on thefront surface of the main body unit of the cassette 4, by a torsion coilspring, not shown, mounted on a rotary shaft of the front lid 11.

On the bottom side of the main body unit of the cassette 4 is mounted aclosure plate 14, as shown in FIGS. 2 and 3. This closure plate 14 isadapted for closing reel shaft insertion openings 12, 13 bored in thebottom surface of the main body unit of the cassette 4 duringnon-loading of the tape cassette 1 on the tape recorder for preventingintrusion of dust and dirt into the main body unit of the cassette 4 forprotecting the magnetic tape 7. The major surface of the closure plate14 is formed with paired insertion openings 15, 16. When the closureplate 14 is moved rearwards relative to the main body unit of thecassette 4, the insertion openings 15, 16 are in register with the reelshaft insertion openings 12, 13, as shown in FIG. 3, to permit areel-driving shaft provided on the tape recorder to be intruded into themain body unit of the cassette 4. If the closure plate 14 is movedforwards of the tape cassette 1 to pull out the magnetic tape 7extending on the front side of the main body unit of the cassette 4 tooutside the main body unit of the cassette 4 to close the lower side ofa spacing 17 faced by tape pull-out means of the tape loading mechanismprovided on the tape recorder, the insertion openings 15, 16 of theclosure plate 14 are offset relative to the reel shaft insertionopenings 12, 13 in the lower half 3 so that the reel shaft insertionopenings 12, 13 are closed by the major surface of the closure plate 14.

If inserted via cassette insertion/ejection opening provided in the mainbody unit of the tape recorder, the tape cassette 1 is held by thecassette holder and loaded on a cassette loading unit provided in themain body unit of the tape recorder. As the cassette holder is moved ina direction towards the cassette loading unit, the front lid 11 isrotated by the lid opening/closing mechanism provided in the main bodyunit of the tape recorder for opening the front side of the main bodyunit of the cassette 4. The magnetic tape 7, housed within the main bodyunit of the cassette 4, is pulled out of the main body unit of thecassette 4 by the tape loading mechanism provided on the tape recorderso as to be extended on the tape running route within the main body unitof the tape recorder and so as to be wrapped around the tape guide drumof the magnetic head device by way of loading.

The tape recorder of the rotary magnetic head type, employing theabove-described tape cassette 1 as a recording medium, according to thepresent invention, includes a cassette holder, not shown, supported forrotation between a first position for insertion/ejection of the tapecassette 1 outside of the casing of the main body unit of the taperecorder and a second position of loading the tape cassette 1 on acassette loading unit 22 provided on a base 21, and an outer lidrotatably mounted on a lid adapted for covering the cassette holderrotated towards the cassette loading unit 22, shown in FIG. 4.

The tape cassette 1 is loaded on the cassette loading unit 22 byrotation of the cassette holder from the first position enablinginsertion/ejection of the tape cassette 1 towards the cassette loadingunit 22. On the cassette loading unit 22 provided on the base 21 arearranged reel shafts 23, 24 engaged with tape reels 5, 6 in the tapecassette 1 for rotating the tape reels 5, 6 for take-up of the magnetictape 7 on one of the tape reels 5, 6. These tape reels 23, 24 arerotated by a driving power transmission unit 152, as later explained,using a capstan motor 25 as a driving source.

On the base 21 is mounted a rotary magnetic head device 26 for facingthe cassette loading unit 22 carrying the reel shafts 23, 24. Themagnetic tape 7 pulled out from the tape cassette is wound about therotary magnetic head device 26. Between the cassette loading unit 22 forthe tape cassette 1 and the rotary magnetic head device 26 are arrangedpaired first and second movable guide blocks 27, 28 of a tape loadingmechanism 20 adapted for pulling out the magnetic tape 7 from the tapecassette 1 for running the tape about a rotary tape guide drum of therotary magnetic head device 26. These first and second movable guideblocks 27, 28 are provided with a tape guide roll 29 and an inclinedguide pin 31 about which the magnetic tape 7 is hooked and which guidesthe magnetic tape 7 over a pre-set angle, such as about 160°, about thetape guide drum of the rotary magnetic head device 26. The first andsecond movable guide blocks 27, 28 are guided by movement guide grooves32, 33 formed in the base 21 so as to be moved between the positionshown in FIG. 4 in which the tape guide roll 29 and the inclined guidepin 31 face the spacing 17 of the tape cassette 1 loaded on the cassetteloading unit 22 and the position in which the tape guide roll 29 and theinclined guide pin 31 are located laterally of the rotary magnetic headdevice 26.

The first and second movable guide blocks 27, 28 are moved along themovement guide grooves 32, 33 by a guide block movement actuating unit151 as now explained. The first and second movable guide blocks 27, 28are moved by a driving motor 34, as a driving source, providedindependently of the capstan motor 25 for running the magnetic tape 7.The guide block movement actuating unit 151 includes a driving motor 34,a cam gear 36 connected thereto via a gear train 35 and a slider 39connected thereto via a rotation actuating member 37a having first andsecond connection arms 37, 38.

The gear train 35 includes a worm gear 41, mounted on a driving shaft ofthe driving motor 34, a first counter gear 42, having coaxial first andsecond gears 42a, 42b, and a second counter gear 43, having coaxialfirst and second gears 43a, 43b. The first gear 43a meshes with thesecond gear 42b of the first counter gear 42. The gear train 35 alsoincludes a third counter gear 44 having coaxial first and second gears44a, 44b and a fourth counter gear 45 meshing with the third gear 44band with the cam gear 36. The first gear 44a meshes with the second gear43b of the second counter gear 43.

The rotation actuating member 37a, interconnecting the gear train 35 andthe cam gear 36, is formed with upstanding first and second connectionarms 37, 38 in a direction of crossing each other, and is substantiallyL-shaped in its entirety, as shown in FIGS. 4 and 5. This rotationactuating member 37a has the proximal end carrying the first and secondconnection arms 37, 38 supported by a pivot 37b provided with base 21 soas to be rotated about the pivot 37b.

The cam gear 36 is formed with a first cam groove 46 for moving themovable guide blocks 27, 28. This first cam groove 46, formed forextending along the rim of the cam gear 36, is engaged by an engagementpin 47 provided on the first connection arm 37 extended from therotation actuating member 37a. The second connection arm 38, extendingin a direction perpendicular to the first connection arm 37 of therotation actuating member 37a, is formed on its one end with anengagement recess 48. This engagement recess 48 is engaged by anengagement pin 49 provided on the slider 39 which is mounted formovement in the directions indicated by arrows X₁ and X₂ in FIG. 4. Thisslider 39 is moved between two positions, that is between the unloadingposition in which the slider is moved in the direction as indicated byarrow X₁ in FIGS. 4 and 5 and the loading position in which the slideris moved in the direction as indicated by arrow X₂ in FIGS. 4 and 5.

On the other hand, the first and second movable guide blocks 27, 28 aremounted on the distal ends of first connection arms 51, 51 for rotationvia pivots 51a, 51a, as shown in FIG. 6, these first connection arms 51,51 having proximal ends supported by the distal ends of secondconnection arms 52, 52 for rotation via pivots 51a, 51a, respectively.These second connection arms 52, 52 are supported for rotation viapivots 53b, 53b on the distal ends of third connection arms 53, 53having proximal ends rotatably supported via pivots 53a, 53a set uprighton the base 21.

On the pivots 53a, 53a supporting the third connection arms 53, 53 arerotatably mounted limiter plates 54, 55, on the outer rim of which areformed gears 54a, 54b meshing with each other, as shown in FIG. 7. Thatis, the third connection arms 53, 53 and the limiter plates 54, 55 aremounted coaxially via pivots 53a, 53a, respectively. Between the thirdconnection arms 53, 53 and the limiter plates 54, 55 are mounted firstand second torsion coil springs 59, 60, respectively. The first torsioncoil spring 59 is mounted by having the distal end of its arm 59aretained by a spring retainer 59b formed by warping the proximal end ofone of the third connection arms 53, 53 and by having the other arm 59cretained by a spring retainer 59d formed on the outer rim of the limiterplate 54. The first torsion coil spring 59 is biased in a direction inwhich its first and second arms 59a, 59c are spaced apart from eachother, so that one of the third connection arms 53, 53 is biased forrotation in a direction indicated by arrow A in FIG. 7 under the bias ofthe first torsion coil spring 59.

A second torsion coil spring 60 is mounted by having the distal end ofits arm 60a retained by a spring retainer 60b formed by warping theproximal end of the opposite side third connection arm 53 and by havingthe opposite side arm 60c retained by a spring retainer 60d formed onthe outer rim of the opposite side limiter plate 55. The second torsioncoil spring 60 is biased in a direction in which its first and secondarms 60a, 60c are spaced apart from each other, so that the other thirdconnection arm 53 is biased for rotation in a direction indicated byarrow B in FIG. 7 under the bias of the second torsion coil spring 60.

The opposite side limiter plate 55 is formed with a cam opening 57 inwhich is engaged a supporting pin 58 provided on the slider 39.

When the first and second movable guide blocks 27, 28 supported by thefirst connection arms 51, 51 connected via second connection arms 52, 52to the third connection arms 53, 53 are moved to the trailing ends ofmovement guide recesses 32, 33, the third connection arms 53, 53 arerotationally biased in the direction indicated by arrows A and B in FIG.7, under the bias of the first and second torsion coil springs 59, 60,for abutting the first and second movable guide blocks 27, 28 againstpositioning members 27a, 28a.

If the driving motor 34 is run in rotation, the cam gear 36 of the guideblock movement actuating unit 151 is rotated via gear train 35 formoving the slider 39 via the first connection arm 37 and secondconnection arm 38. If the slider 39 is moved in this manner, theopposite side limiter plate 55, in the cam opening 57 of which isengaged the supporting pin 58 provided on the slider 39, is rotatedabout pivot 53a as center of rotation. By rotation of the opposite sidelimiter plate 55, the limiter plate 54, provided with a gear 54a meshingwith a gear 55a provided on the limiter plate 55, is rotated in theopposite direction to the direction of rotation of the other limiterplate 55, about the pivot 53a as center of rotation. The first andsecond movable guide blocks 27, 28 are moved by the first to thirdconnection arms 51 to 53, under guidance by the movement guide grooves32, 33, from the position facing the spacing 17 of the tape cassette 1loaded on the cassette loading unit 22 to the position of FIG. 5laterally of the rotary magnetic head device corresponding to theloading end position of the magnetic tape 5. The result is that themagnetic tape 7 within the tape cassette 1 is pulled out from the tape,cassette 1 so as to be wrapped about the tape guide drum of the rotarymagnetic head device 26, as shown in FIG. 5.

Between the cassette loading unit 22 and the rotary magnetic head device26 are rotatably mounted a pinch roll supporting arm 63, a tape guidesupporting arm 65, carrying on its distal end an upstanding tape guide64, and a tape guide supporting arm 67, carrying at its distal end atape guide 66. The pinch roll supporting arm 63 has mounted on itsdistal end a pinch roll 62 pressed against a capstan shaft 61 forclinching the magnetic tape 7 for assuring constant speed running of themagnetic tape 7. The capstan shaft 61 is a driving shaft of the capstanmotor 25 adapted for running the magnetic tape 7.

The pinch roll supporting arm 63 has its proximal end supported by apivot 68 so that the pinch roll supporting arm 63 is rotated about thepivot 68 as center of rotation. On this pivot 68 is rotatably mounted athrusting lever 69, coaxially with the pinch roll supporting arm 63, forthrusting the tape guide supporting arm 65. On one distal end of thethrusting lever 69 is mounted a thrusting lug 71 adapted for thrustingthe tape guide supporting arm 65. On the tape guide supporting arm 65 ismounted a toggle spring 74 between a retention lug 72 provided on thetape guide supporting arm 65 and a retention lug 73 set upright on thebase 21.

When the first and second movable guide blocks 27, 28 are moved from theposition facing the spacing 17 of the tape cassette 1 as shown in FIG. 4to the loading end position for the magnetic tape 7 as shown in FIG. 5in which the first and second movable guide blocks 27, 28 are positionedlaterally of the rotary magnetic head device 26, the pinch rollsupporting arm 63 is enabled to be rotated from the position towards thecassette loading unit 22 shown in FIG. 4 towards the position in whichthe pinch roll 62 is pressed against the capstan shaft 61 as shown inFIG. 5. The thrusting lever 69 then is rotated from the position towardsthe cassette loading unit 22 shown in FIG. 4 to the position towards thecapstan shaft 61 shown in FIG. 5. The thrusting lever 69 then thruststhe tape guide supporting arm 65 by the thrusting lug 71. The tape guidesupporting arm 65 is moved under the bias of the toggle spring 74 fromthe position shown in FIG. 4 in the direction of causing the magnetictape 7 to be taken up on the capstan shaft 61 as shown in FIG. 5.

The tape guide supporting arm 67 is rotated about a pivot 75 as thecenter of rotation so that the tape guide 66 is moved from a positiontowards the inside of the base 21 as shown in FIG. 4 to a positionoutwardly of the base 21 as shown in FIG. 5. The tape guide supportingarm 67 also has its rotational position controlled by a toggle spring 84installed between a retention lug 82 provided on the tape guidesupporting arm 67 and a retention lug 83 set upright on the base 21.Rotation of the tape guide supporting arm 67 is by a rotary lever 76. Onone distal end of the rotary lever 76 is set a guide pin 77 engaged in aguide opening 85 bored in the tape guide supporting arm 67. Also, thetape guide supporting arm 67 is rotated about the pivot 75 set on thebase 21. On the lateral edge on the proximal end of the rotary lever 76is formed a recessed cam 79 abutted by a thrusting pin 81 provided onthe slider 39.

With the tape guide supporting arm 67, associated with the slider 39,when the slider 39 is moved in the direction of arrow X₂ in FIG. 4, thethrusting pin 81 thrusts the cam 79 of the rotary lever 76 to rotate therotary lever 76 in the direction indicated by arrow X₃ in FIG. 4, at thesame time as the tape guide supporting arm 67 is rotated in the samedirection as the rotary lever 76. This shifts the tape guide 66 from theposition inwardly of the base 21 shown in FIG. 4 to the positionoutwardly of the base 21 as shown in FIG. 5.

With the tape recorder, having the above-described tape loadingmechanism 20, if the tape cassette 1 is loaded on the cassette loadingunit 22, the magnetic tape 7 is pulled outwards by the tape guide roll29 and the inclined guide pin 31 of the first and second movable guideblocks 27, 28 so as to be wrapped around the rotary magnetic head device26. The magnetic tape 7 is placed around- the tape guide 66 and a tapeguide 86 set on the base 21 so as to be wound about the rotary magnetichead device 26 via the tape guide roll 29 and the inclined guide pin 31of the first movable guide block 27. The magnetic tape 7, reeled outfrom the rotary magnetic head device 26, is clinched between the capstanshaft 61 and the pinch roll 62, via the inclined guide pin 31 of thesecond movable guide block 28, tape guide roll 29 and tape guide 62a seton the base 21, so as to be placed about the tape guide pin 64. Themagnetic tape 7 then reaches the take-up side tape reel 24 on thetake-up side within the tape cassette 1.

The driving power transmission unit 152 for rotating the reel shafts 23,24 as the capstan motor 25 as a driving source is explained by referringto FIG. 6 showing the state of loading the magnetic tape 7 on the taperunning route of the main body unit of the tape recorder.

Referring to FIG. 6, the driving power transmission unit 152 includes acapstan gear 87, mounted on the capstan shaft 61, as a driving shaft ofthe capstan motor 25, for rotation in unison with the capstan shaft 61,and a first drive transmission gear 88 formed as one with coaxial firstgear 88a of larger diameter and second gear 88b of lesser diameter. Thefirst gear 88a meshes with the capstan gear 87. The driving powertransmission unit 152 also includes a second drive transmission gear 89meshing with the second gear 88b of the first drive transmission gear 88and a third drive transmission gear 91 meshing with the second drivetransmission gear 89. The driving power transmission unit 152 furtherincludes a fourth drive transmission gear 93 carried by a pivot 92operating as a fulcrum of rotation of a rotary base block 98 which willbe explained subsequently in detail. This fourth drive transmission gear93 has a first gear portion 93a of larger diameter and a second gearportion 93b of lesser diameter, mounted coaxially with each other, withthe first gear portion 93a and the second gear portion 93b meshing withthe a third drive transmission gear 91 and with a clutch gear 99,carried by the rotary base block 98, respectively.

The clutch gear 99 will be explained subsequently in detail.

On the reel shafts 23, 24 are coaxially mounted reel shaft gears 94, 95,meshing with reel shaft driving gears 96, 97, respectively. These reelshaft driving gears 96, 97 are rotatably carried on the base 21 viapivots 96a, 97a, respectively. When the rotary base block 98 is rotatedabout the pivot 92 as center, the reel shafts 23, 24 mesh with one ofthe reel shaft driving gears 96, 97 to rotate the driving gear.

Referring to FIGS. 6 to 8 and FIG. 13, a reel shaft selection unit 153for selecting one of the reel shafts 23, 24 is explained in detail.

Referring to FIG. 6, the reel shaft selection unit 153 includes a camgear 36, a slider 39 constituting the guide block movement actuatingunit 151 and a reel shaft selecting slider 101 movably mountedside-by-side with the slider 39. The guide block movement actuating unit151 is moved via the rotation actuating member 37a and the engagementpin 47 of the first connection arm 37 of which is engaged in the firstcam groove 46 in the cam gear 36. The reel shaft selection unit 153 alsoincludes a reel shaft selection slider 101 movably mounted side-by-sidewith respect to the slider 39, a rotary lever 102 rotatably mounted onthe reel shaft selection slider 101 and a connection member 103rotatably mounted on the reel shaft selection slider 101 for rotatablyinterconnecting the reel shaft selection slider 101 and the rotary baseblock 98.

On the inner peripheral side of the above-mentioned first cam groove 46of the cam gear 36 is formed a second cam gear 104. This, second camgear 104 is engaged by an engagement pin 105 set upright on one end ofthe reel shaft selection slider 101. By rotation of the cam gear 36, thereel shaft selection slider 101 is rotated in the direction indicated byarrow X₁ or X₂ in FIG. 6 for rotating the rotary base block 98 mountedvia connection member 103 in the direction indicated by arrow X₃ or X₄in FIG. 6.

The reel shaft selection slider 101 is mounted side-by-side with theslider 39 on the base 21, for movement in the direction indicated byarrow X₁ or X₂ in FIG. 6. This reel shaft selection slider 101 isselectively moved to three positions, namely a first position in whichthe slider has been moved in the direction indicated by arrow X₁ in FIG.6 for running the magnetic tape 7 at a constant velocity in the forwarddirection, a second position in which the slider has been moved in thedirection indicated by arrow X₂ in FIG. 6 for running the magnetic tape7 in the reverse direction and a third neutral position between thesefirst and second positions. On the reel shaft selection slider 101 ismounted the rotary lever 102 for rotation in the direction indicated byarrow X₅ or X₆ in FIG. 6 with a pivot 106 set thereon as the center ofrotation. Between the rotary lever 102 and the reel shaft selectionslider 101 is mounted a toggle spring 107 for biasing the rotary lever102 in the direction indicated by arrow X₆ in FIG. 6. On the rotarylever 102 is also set a thrust pin 108 which is thrust by a cam portion109 provided on the slider 39 provided side-by-side above the reel shaftselection slider 101 in FIG. 6. The cam portion 109 is formed with aninclined surface protruded towards the reel shaft selection slider 101.When the slider 39 is moved in the direction indicated by arrow X₁ inFIG. 6, for example, the thrust pin 108 is thrust by thee cam portion109 to rotate the rotary lever 102 in the direction indicated by arrowX₅ in FIG. 6 against the bias of the toggle spring 107.

Towards the base 21, a pivot 111 is set on the reel shaft selectionslider 101, and the connection member 103 is rotatably mounted with thispivot 111 as the center of rotation. On the connection member 103 isformed a control pin 112 which is exposed further to outside via arecess 113 formed below the reel shaft selection slider 101 in FIG. 6and an opening 114 constituted by an end face of the rotary lever 102partially covering the recess 113. On the side of the connection member103 not carrying the pivot 111 is mounted the rotary base block 98, forrotation in the direction indicated by arrow X₃ or X₄ in FIG. 6, withthe pivot 110 as the center of rotation.

The rotary base block 98 is mounted for rotation in the directionindicated by arrow X₃ or X₄ in FIG. 6, by the above-mentioned capstanmotor 25 as a driving source, with the pivot 92 of the fourth drivetransmission gear 93 as the center of rotation. The fourth drivetransmission gear 93 constitutes the driving power transmission unit 152causing rotation of the reel shafts 23, 24. This rotary base block 98 isrotated via the connection member 103 by movement of the reel shaftselection slider 101 in the direction indicated by arrow X₁ or X₂ inFIG. 6. The rotary base block 98 is provided with the above-mentionedfourth drive transmission gear 93 and the clutch gear 99.

Referring to FIG. 7, the clutch gear 99 includes an upper gear portion117, carried by an upper shaft 116 set on the rotary base block 98, anda lower gear portion 121 carried by a lower shaft 119 set on a baseblock 118 formed as-one with the pivot 93. Between the upper gearportion 117 and the rotary base block 98 is mounted a first compressioncoil spring 122. Similarly, between the lower gear portion 119 and thebase block 118 is mounted a second compression coil spring 123. Onfacing surfaces of the upper gear portion 117 and the lower gear portion121 are mounted friction members 124, 125 formed of a material having ahigh frictional coefficient, such as felt. The upper gear portion 117and the lower gear portion 119 are thrust towards each other under apre-set bias so that the friction members 124, 125 are in pressurecontact with each other. The upper gear portion 117 meshes with the gearportion 93b of the fourth drive transmission gear 93, while the lowergear portion 119 meshes with one of the reel shaft driving gears 96, 97.If a larger load is applied on the lower gear portion 119, there isgenerated slip between the frictional member 125 of the lower gearportion 119 and the frictional member 124 of the upper gear portion 117to prevent a large load from being applied against the upper gearportion 117.

Referring to FIG. 6, the capstan motor 25 is driven for rotating theclutch gear 99 via the driving power transmission unit 152 rotating thereel shafts 23, 24 for rotating the rotary base block 98 provided withthe clutch gear 99 in the direction indicated by arrow X₃ or X₄ in FIG.6. The clutch gear 99 meshes with one of the reel shaft driving gears96, 97. The rotary base block 98 also is rotated compulsively in thedirection indicated by arrow X₃ or X₄ by movement of the reel shaftselection slider 101 in the direction indicated by arrow X₁ or X₂ inFIG. 6.

The operation of the above-described reel shaft selection unit 153 isexplained with reference to FIGS. 6 and 9 to 13.

First, the loading start position of loading the magnetic tape 7 on thetape running route on the base 21, as shown in FIG. 5, with the the tapecassette 1 loaded on the cassette loading unit 22 of the tape recorder,is explained with reference to FIG. 9.

In this state, the slider 39 is at the unloading position in which theslider has been moved in the direction of arrow X₁ in FIG. 9. On theother hand, the reel shaft selection slider 101 has been moved in thedirection of arrow X₂ in FIG. 9. At this time, the rotary lever 102 hasthe thrust pin 108 thrust by the cam portion 109 provided on the slider39 and is thereby rotated in the direction of arrow X₅ in FIG. 9. On theend face of the rotary lever 102 is abutted the control pin 112. Therotary base block 98 is at an intermediate position such that the clutchgear 99 is not engaged with the reel shaft driving gear 96 nor with thereel shaft driving gear 97. Thus, the tape reels 5, 6 of the tapecassette 1 are in the rotatable state, such that, by movement of thefirst and second movable guide blocks 27, 28 from the position facingthe spacing 17 of the tape cassette 1 to the position laterally of therotary magnetic head device 26, the tape reels 5, 6 pull out themagnetic tape 7 from the tape cassette 1 to the tape running route shownin FIG. 5, so that the tape is wound about and can run along the tapeguide drum of the rotary magnetic head 26.

When the magnetic tape 7 is wound about and can run along the tape guidedrum of the rotary magnetic head device 26, the tape recorder is firstset to the halted state. In this halted state, the reel shaft selectionunit 153 shifts the slider 39 in the direction indicated by arrow X₂ inFIG. 10 from the unloading position to the loading position. The reelshaft selection slider 101 is moved in the direction indicated by arrowX₁ in FIG. 10 to an intermediate position. The reel shaft selectionslider 101, thus moved in the direction indicated by arrow X₁ in FIG.10, rotates the rotary base block 98 in the direction indicated by arrowX₃ in FIG. 10, from the state shown in FIG. 8, as far as the neutralposition. Therefore, the clutch gear 99 is engaged with none of the reelshaft driving gears 96, 97. By movement of the slider 39 in thedirection indicated by arrow X₂ in FIG. 10 and by movement of the reelshaft selection slider 101 in the direction indicated by arrow X₁ inFIG. 10, the thrust pin 108 is not thrust by the cam portion 109, suchthat the rotary lever 102 is rotated in the direction indicated by arrowX₆ in FIG. 10 under the bias of the toggle spring 107. In this state,the control pin 112 is abutted against the end face of the rotary lever102, while being controlled by the recess 113.

Meanwhile, during the fast feed mode of running the magnetic tape 7 atan elevated speed in the forward direction, and during the rewind modeof running the magnetic tape 7 at an elevated speed in reverse, the reelshaft selection slider 101 is put at the neutral position in which ithas been moved in the direction indicated by arrow X₁ in FIG. 10, withthe clutch gear 99 meshing with none of the reel shaft driving gears 96,97.

Referring to FIG. 11, the operational state of the tape recorder onselection of the recording and/or reproducing mode is now explained, inwhich the magnetic tape 7 is run from the stop mode in the forwarddirection of arrow S in FIG. 5 at a constant velocity as from the tapereel 23 towards the opposite side tape reel 24 for recording and/orreproducing information signals.

If the recording and/or reproducing mode in the forward direction of thetape recorder of the present invention is selected, the driving motor 34is run in rotation for rotating the cam gear 36 via gear train 35 in thedirection indicated by arrow R₁ in FIG. 11. At this time, the slider 39,connected to the cam gear 36 via the rotation actuating member 37a,keeps the magnetic tape 7 loaded on the tape running route, as shown inFIG. 11. Since the rotation actuating member 37a is maintained at thistime in a state in which the engagement pin 47 is engaged in aconcentric portion 46a of the cam groove 46, the rotation actuatingmember 37a is not rotated about the pivot 37b, even if the cam gear 36is rotated in the direction indicated by arrow R₁ in FIG. 6. Since therotation actuating member 37a is not rotated, the slider 39 of the reelshaft selection unit 153 is maintained in a state in which the magnetictape 7 has been loaded on the tape running route. On the other hand,since the reel shaft selection slider 101 has the engagement pin 105engaged in the second cam groove 104 of the cam gear 36, the engagementpin 105 is moved along the second cam groove 104, by rotation of the camgear 36 in the direction indicated by arrow R₁ in FIG. 11, so that thereel shaft selection slider 101 is moved in the direction indicated byarrow X₁ in FIG. 11. When the reel shaft selection slider 101 is movedto the left-side end in FIG. 11, the rotary base block 98 is rotatedfrom the intermediate position shown in FIG. 10 in the directionindicated by arrow X₃ in FIG. 11. The clutch gear 99 is engaged with thereel shaft driving gear 97 for rotating the rewind side reel shaft 24.As in the state shown in FIG. 10, the rotary lever 102 is kept in astate in which it has been rotated in the direction indicated by arrowX₆ in FIG. 1. At this time, the connection member 103 has the controlpin 113 abutted against the end face of the rotary lever 102, whilehaving its movement controlled by the recess 113. Thus, the connectionmember 103 is not rotated by movement of the reel shaft selection slider101. The rotary base block 98 is rotated only by movement of the reelshaft selection slider 101.

If the magnetic tape 7 is run in the forward direction in the directionindicated by arrow S in FIG. 5, the winding diameter of the magnetictape 7 on the tape reel 5 engaged with the takeup side reel shaft 24 isvaried with the winding amount of the magnetic tape 7. If the amount ofthe magnetic tape 7 taken up on the take-up side tape reel 5 isincreased, the magnetic tape 7 is taken up on the tape reel 5 at ahigher velocity than the constant tape running speed by the capstanshaft 61, so that a tension more than is necessary is applied to themagnetic tape 7. Since the slip is produced at this time between thefrictional members 124, 125 of the clutch gear 99 engaged with the reelshaft driving gear 97, such excess tension can be prevented from beingapplied to the magnetic tape 7. This applies for the case in which themagnetic tape 7 as later explained is run in the reverse direction.

Referring to FIG. 12, the operational state on selection of the reverserunning mode in which the magnetic tape 7 is run from the opposite sidetape reel 24 towards the tape reel 23 in the reverse direction indicatedby arrow T in FIG. 5 for searching the information recorded on themagnetic tape 7 or rewriting the subcode, is explained.

If the running mode in the reverse direction of the tape recorderaccording to the present invention is selected, the driving motor 34 isrun in rotation, so that the cam gear 36 is run in rotation by thedriving motor 34 in the direction indicated by arrow R₁ in FIG. 12 viagear train 35. The slider 39 connected to the cam gear 36 via therotation actuating member 37a keeps the magnetic tape 7 loaded on thetape running route, as shown in FIG. 12. Since the engagement pin 47 iskept engaged with the concentric portion 46a of the cam groove 46, therotation actuating member 37a is not rotated about the pivot 37b even ifthe cam gear 36 is rotated in the direction indicated by arrow R₁ inFIG. 6. Since the rotation actuating member 37a is not rotated, theslider 39 constituting the reel shaft selection unit 153 is kept in thestate of loading the magnetic tape 7 on the tape running route, as whenthe recording and/or reproducing mode of running the magnetic tape inthe forward direction at the constant running velocity is selected, asdescribed above. Since the engagement pin 105 is engaged in the secondcam groove 104 of the cam gear 36, the engagement pin 105 is moved alongthe second cam groove 104 by rotation of the cam gear 36 in thedirection indicated by arrow R₁ in FIG. 11, the reel shaft selectionslider 101 being then moved in the direction indicated by arrow X₂ inFIG. 12. When the reel shaft selection slider 101 is moved up to theright-hand side end in FIG. 12, the clutch gear 99 is engaged with thereel shaft driving gear 96 for rotating the rotary base block 98 fromthe intermediate position shown in FIG. 10 in the direction indicated byarrow X₄ in FIG. 1 1 for rotating the supply side reel shaft 24. Therotary lever 102 is kept in the state in which the lever has beenrotated in the direction indicated by arrow X₆ in FIG. 11 under the biasof the toggle spring 107, as in the state shown in FIG. 10. Since thecontrol pin 113 compresses at this time against the end face of therotary lever 102 and is simultaneously controlled in its movement by therecess 113, the connection member 103 is not rotated by movement of thereel shaft selection slider 101. The rotary base block 98 is rotatedonly by the movement of the reel shaft selection slider 101.

The state in which the running mode in the reverse direction has beenselected is substantially equivalent to the state in which the magnetictape 7 pulled out to the tape running route is taken up in the tapecassette 1 order to start the uploading. That is, the slider 39 and thereel shaft selection slider 101 are put in the positions shown in FIG.11.

The unloading operation of taking up the magnetic tape 7 pulled out tothe tape running route within the tape cassette 1 is explained withreference to FIG. 13.

For unloading, the driving motor 34 is run in rotation for rotating thecam gear 36 via gear train 35 in the direction indicated by arrow R₁ inFIG. 13. When the cam gear 36 is rotated in the direction indicated byarrow R₁ in FIG. 13, the engagement pin 47 of the rotation actuatingmember 37a engaged in the first cam groove 46 is moved from theconcentric portion 46a to an offset portion 46b of the first cam groove46 and is moved along this offset portion 46b to rotate the rotationactuating member 37a in the direction indicated by arrow G in FIG. 5.

When the rotation actuating member 37a is run in rotation in thedirection indicated by arrow G in FIG. 5, the slider 39 connected to therotation actuating member 37a is moved in the direction indicated byarrow X₁ in FIG. 13. At this time, the pinch roll supporting arm 63connected via a link mechanism, not shown, to the cam gear 36, isrotated in a direction away from the capstan shaft 61 for moving thepinch roll 62 away from the capstan shaft 61 to release the clinching ofthe magnetic tape 7.

When the slider 39 is moved in the direction indicated by arrow X₁ inFIG. 13, the limiter plate 54 connected to the slider 39 is rotated inthe direction opposite to that indicated by arrow B in FIG. 7 to rotatethe opposite side third connecting arm 53 in the direction opposite tothat indicated by arrow B. The limiter plate 54, having a gear 55aengaged in a gear portion 55b of the limiter plate 55, is rotated intimed relation to the limiter plate 55 in the direction opposite to thedirection of arrow A in FIG. 7 for rotating the third connecting arm 53in the direction opposite to the direction of arrow A.

When the paired third connection arms 53, 53 are rotated in thedirection opposite to arrow B and in the direction opposite to arrow Ain FIG. 7, the second connection arms 52, 52, connected to these thirdconnection arms 53, 53, are rotated in the direction opposite to arrow Band in the direction opposite to arrow A in FIG. 7. The movable guideblocks 27, 28, supported by the distal ends of the first connection arms51, 51, connected to the second connection arms 52, 52, are moved fromthe position laterally of the rotary magnetic head device 26 towards thecassette loading unit 22, under guidance by the movement guide grooves32, 33, up to the position facing the spacing 17 of the tape cassette 1loaded on the cassette loading unit 22.

At this time, the reel shaft selection slider 101 has been moved in thedirection indicated by arrow X₂ in FIG. 13, as in the position shown inFIG. 12 associated with selection of the reverse running mode of runningthe magnetic tape 7 in the reverse direction. Since the reel shaftselection slider 101 has been moved in the direction indicated by arrowX₂ in FIG. 13, the rotary lever 102 has the thrust pin 108 thrust by thecam portion 109 of the slider 39 and hence is in the state of havingbeen rotated in the direction indicated by arrow X₅ in FIG. 13. At thistime, the control pin 112 is positioned in the opening 114 delimited bythe end face of the rotary lever 102 and the recess 113 formed in thereel shaft selection slider 101 so as to be moved within the extent ofthe opening 114.

Since the reel shaft selection slider 101 is in a inoperative state, therotary base block 98 is maintained in the state of having been rotatedin the direction indicated by arrow X₄ in FIG. 13, so that the clutchgear 99 is kept engaged with the reel shaft driving gear 96.

Meanwhile, the capstan motor 25 continues to be rotated during theoperation of unloading the magnetic tape 7 pulled out to the taperunning route of the main body unit, so that the tape supply side reelshaft 23 is rotated via the driving power transmission unit 152, inorder to take up the magnetic tape 7 on the supply side tape reel 6.

If, during the unloading of the magnetic tape 7, the takeup speed on thesupply side tape reel 6 is deviated from the movement speed of the firstand second movable guide blocks 27, 28 to apply a large tension on themagnetic tape 7, there is produced a slip between the frictional members124, 125 to prevent a large tension from being applied to the magnetictape 7.

The operation in which the magnetic tape 7 is taken up in the tapecassette 1, the cassette holder holding the tape cassette 1 is moved ina direction away from the cassette loading unit 22, the tape cassette isejected, and a new tape cassette 1 is held in the cassette holder andloaded on the cassette loading, unit 22 by way of loading the magnetictape 7, is hereinafter explained.

When the tape cassette 1 previously loaded on the cassette loading unit22 has been taken out, the rotary lever 102 constituting the reel shaftselection unit 153 has been rotated in the direction indicated by arrowX₅ in FIG. 13, with the thrust pin 108 being thrust against the camportion 109 of the slider 39 and rotated in the direction indicated byarrow X₅ in FIG. 13, such that the control pin 112 is movable within theextent of the opening 114 delimited by the end face of the rotary lever102 and the recess 113 formed in the reel shaft selection slider 101.

If the capstan motor 25 is run in rotation, the clutch gear 99 is run inrotation via the driving power transmission unit 152, so that the rotarybase block 98 is rotated in the direction indicated by arrow X₃ in FIG.13, about the pivot 92 as the center of rotation, from the state inwhich the clutch gear 99 meshes with the reel shaft driving gear 96 tothe neutral position in which the clutch gear is engaged with none ofthe reel shaft driving gears 96, 97, as shown in FIG. 9. By the rotationof the rotary base block 98 under the driving power of the capstan motor25 from the position of meshing with the reel shaft driving gear 96 tothe neutral position, the magnetic tape 7 is pulled out from the tapecassette 1 loaded in the cassette loading unit 22 so as to be extendedon the tape running route in the main body unit and taken up on the tapeguide drum of the rotary magnetic head device 26, by way of tapeloading, as shown in FIG. 9.

Since the magnetic tape 7 can be switched from the unloading state tothe loading state for the magnetic tape 7 simply by rotating the rotarybase block 98 by the capstan motor 25 without employing the reel shaftselection unit 153 made up of the cam gear 36, slider 39 and the reelshaft selection slider 101, prompt tape loading can be achieved.Moreover, since the first and second cam grooves 46, 104 provided in thecam gear 36 controlling the movement of the slider 39 and the reel shaftselection slider 101 can be simplified in structure, the operating modeof the tape recorder can be switched promptly.

Referring to FIG. 14, a tape recorder of the rotary magnetic headsystem, provided with a tensioning mechanism 200 for imparting backtension to the magnetic tape 7 run in the forward or reverse directionis explained.

In the tape recorder of the rotary magnetic head system, parts orcomponents similar to those of the above-described tape recorder of therotary magnetic head system are denoted by the same reference numeralsand are not explained specifically.

Referring to FIG. 14, the tensioning mechanism 200 includes a firstclutch gear 201 meshing with the reel shaft gear 94 adapted for rotatingthe supply side reel shaft 23 for imparting back tension to the magnetictape 7 and a second clutch gear 202 meshing with the reel shaft gear 95adapted for rotating the take-up side reel shaft 24 for imparting backtension to the magnetic tape 7.

Referring to FIG. 15, the first gear 201 has a first gear portion 204carried by a shaft 203 set on the base 21 and a second gear portion 205mounted coaxially with the first gear portion 204. Between the firstgear portion 204 and the base 21 is installed a thrusting spring 206thrusting the second gear portion 205 towards the first gear portion204. Between the first gear portion 204 and the second gear portion 205is arranged a frictional member 207 having a high frictionalcoefficient, such as felt. That is, the second gear portion 205 isthrust by the thrusting spring 206 under the biasing force towards thefirst gear portion 204 so that the frictional member 107 is brought intopressure contact with the first gear portion 204. The first gear portion204 meshes with the supply side reel gear 94.

The second gear portion 205 is selectively engaged by a first lock lever208 adapted for locking the rotation of the first clutch gear 201. Thefirst lock lever 208 is rotatably carried by a pivot 209 set on the base21, as shown in FIGS. 14 and 15. The first lock lever 208 carries, onits distal end, a retention portion 213 retained by the second gearportion 205 of the first lock lever 208. The first lock lever 208 isbiased in the direction indicated by arrow P in FIG. 14, that is in adirection towards the first gear portion 205 of the first clutch gear201, by a torsion coil spring 216 having one end retained by a guideshaft 211 adapted for guiding the movement of the reel shaft selectionslider 101 and having its other end retained by a retention lug 212provided on the first lock lever 208.

On the proximal end of the first lock lever 208 is provided a camportion 214 made up of an inclined surface section 214a and a horizontalsurface section 214b. On this cam portion 214 is abutted a first controllug 215 set on one surface of the reel shaft selection slider 101. Thatis, the first lock lever 208 is inhibited in rotation in the directionindicated by arrow P in FIG. 14 when the first control lug 215 isabutted against the horizontal surface section 214b, while it is rotatedin the direction indicated by arrow P in FIG. 14 so as to be retained bythe second gear portion 205 of the first clutch gear 201 when the firstcontrol lug 215 is abutted against the inclined surface section 214a.When inhibited in rotation by the first lock lever 208, the first clutchgear 201 causes the slip to be produced between the frictional member207 and the first and second gears 204, 205 to apply a load on the reelshaft 94 meshing with the first gear portion 204.

The first lock lever 208 is mounted on the base 21 by a screw 218 usinga mounting member 217.

The second clutch gear 202 meshes with a reel shaft gear 95 adapted forrotating the take-up side reel shaft 24. The second clutch gear 202 isthe same in structure as the above-described first clutch gear 201 andhence is not explained specifically.

The second clutch gear 202 is selectively engaged by a second lock lever221 adapted for locking the rotation of the second clutch gear 202. Thesecond lock lever 221 is rotatably carried by a pivot 222 set on thebase 21, as shown in FIG. 14. The second lock lever 221 carries, on itsdistal end, a retention portion 223 retained by the second gear portion205 of the second clutch gear 202.

The second lock lever 221 is biased towards the second clutch gear 202,that is in the direction indicated by arrow Q in FIG. 14, by a torsioncoil spring 226 having its one end retained by a guide shaft 224 adaptedfor guiding the movement of the slider 39 and having its other endretained by a retention lug 225 provided on the second lock lever 221.On the proximal end of the second lock lever 221 is provided a camportion 227 made up of an inclined surface section 227a and a horizontalsurface section 227b. This cam portion 227 is abutted by a secondcontrol lug 228 set on the opposite side of the reel shaft selectionslider 101. That is, the second lock lever 221 is inhibited in rotationin the direction indicated by arrow Q in FIG. 14 when the second controllug 228 is abutted against the horizontal surface section 227b, while itis rotated in the direction indicated by arrow Q in FIG. 14 so as to beretained by the second gear portion 202 when the second control lug 228is abutted against the inclined surface section 227a. When inhibited inrotation by the second lock lever 221, the second clutch gear 202 causesthe slip to be produced between the frictional member 207 and the firstand second gears 204, 205 to apply a load on the reel shaft 95 meshingwith the first gear portion 204.

The above-described tensioning mechanism 200 operates as follows:

In the loading start state in which the magnetic tape 7 is pulled outand extended on the pre-set tape running route, as shown in FIG. 9, thereel shaft selection slider 101 has been moved in the directionindicated by arrow X₂ in FIG. 9. At this time, the first lock lever 208is in such a state in which the control lug 215 provided on one side ofthe reel shaft selection slider 101 is abutted against the horizontalsurface section 214b of the cam portion 214 so as to be separated awayfrom the first clutch gear 201.

The second lock lever 221 is in such a state in which the control lug228 provided on the opposite side of the reel shaft selection slider 101is abutted against the inclined surface section 227a of the cam portion227 and is rotated under the bias of the torsion coil spring 226 towardsthe second clutch gear 202 into engagement with the second clutch gear202. That is, the supply side first clutch gear 201 is enabled to berotated without being locked by the first lock lever 208 to enablerotation of the reel shaft gear 94 meshing with the first clutch gear201.

With the movable guide block movement actuating unit 151, if the drivingmotor 34 is run in rotation, the cam gear 36 is run in rotation via geartrain 35, so that the slider 39 is moved via rotation actuating member37a, as shown in FIGS. 4 and 5. When the slider 39 is moved, the limiterplate 55, having the cam opening 57 engaged by the supporting pin 58provided on the slider 39, is rotated about the pivot 53a as the centerof rotation. By rotation of the limiter plate 55, the limiter plate 54,having the gear 54a meshing with the gear portion 55a of the limiterplate 55, is rotated in the opposite direction to the direction ofrotation of the limiter plate 55, with the pivot 53a as the center ofrotation. The first and second movable guide blocks 27, 28 are moved viathe first to third connection arms 51 to 53, under guidance by themovement guide grooves 32, 33, between the position facing the spacing17 of the tape cassette 1 loaded on the cassette loading unit 22 asshown in FIG. 4 and the position corresponding to the loading endposition of the magnetic tape 7 laterally of the rotary magnetic headdevice 26 as shown in FIG. 5. This pulls the magnetic tape 7 in the tapecassette 1 from the tape cassette 1 so as to be wound about the tapeguide drum of the rotary magnetic head device 26, as shown in FIG. 5.

When the running of the magnetic tape 7 about the tape guide drum of therotary magnetic head device 26 ceases, the reel shaft selection slider101 is put at an intermediate position of movement in the directionindicated by arrow X₁ in FIG. 10. At this time, the first lock lever 208is spaced apart from the first clutch gear 201, because the control lug215 provided on one lateral side of the reel shaft selection slider 101is abutted against the horizontal surface section 214b of the camportion 214. The second lock lever 221 is spaced apart from the secondlock lever 221 because the control lug 228 provided on the opposite sideof the reel shaft selection slider 101 is abutted against the horizontalsurface section 227b of the cam portion 227.

If the fast feed mode or the rewind mode is selected, and the capstanmotor 34 is run in rotation, the rotary base block 98 is rotated in thedirection indicated by arrow X₃ or X₄ in FIG. 10, depending on thedirection of rotation of the capstan motor 34, so that the clutch gear99 is selectively engaged with one of the reel shaft driving gears 96,97 to run the magnetic tape 7 at an elevated velocity in the forward orreverse direction. The magnetic tape 7 is taken up on the takeup sidetape reel 6 or on the supply side tape reel 5. Since the reel shaftselection unit 153 again is not in operation neither, the first locklever 208 nor the second lock lever 221 is engaged with the second gearportions 205, 205 of the first clutch gear 201 and the second clutchgear 202, with the reel shaft gears 94, 95 being enabled to be rotatedto enable high-speed running of the magnetic tape 7.

If, from the stop mode, the recording and/or reproducing mode, in whichthe magnetic tape 7 is run in the forward direction, that is from thesupply side tape reel 5 towards the takeup moved side tape reel 6 forrecording and/or reproducing information signals, the reel shaftselection slider 101, having the engagement pin 105 engaged in thesecond cam groove 104 of the cam gear 36, is moved in the directionindicated by arrow X₂ in FIG. 11, by the engagement pin 105 being movedalong the second cam groove 104 with rotation in the direction of arrowR₁ in FIG. 11 of the cam gear 36, as shown in FIG. 11.

At this time, the first lock lever 208 is rotated under the bias of thetorsion coil spring 216 in the direction indicated by arrow P in FIG.14, by the control lug 215 on one side of the reel shaft selectionslider 101 abutted against the inclined surface section 214a of the camportion 214, the retention portion 213 then engaging with the secondgear portion 205 of the first clutch gear 201. The second lock lever 221is spaced apart from the second clutch gear 202 by the control lug 228on the opposite side of the reel shaft selection slider 101 abuttedagainst the horizontal surface section 227b of the cam portion 227.

If, in this state, the magnetic tape 7 is run at a constant velocity inthe forward direction, the first clutch gear 201 has the first gearportion 204 rotated with rotation of the reel shaft gear 94 and has thesecond gear portion 205 locked against rotation by the first lock lever208, so that a slip is generated between the first gear portion 204 andthe second gear portion 205 to generate a pre-set load. Thus, when themagnetic tape 7 is taken up on the takeup side tape reel 6, it is runwith a back tension and taken up on the tape reel 6 in a trim windingstate on the tape reel 6 without producing slack during rewinding.

It is assumed that the magnetic tape 7 is run in reverse, that is fromthe takeup side tape reel 6 towards the supply side tape reel 23. Inthis case, since the reel shaft selection slider 101 has the engagementpin 105 engaged in the cam groove 104 of the cam gear 36, the engagementpin 105 is moved along the second cam groove 104 in the directionindicated by arrow X₂ in FIG. 12 by the rotation of the cam gear 36 inthe direction indicated by arrow R₁ in FIG. 12. At this time, since thefirst lock lever 208 is spaced apart from the first clutch gear 201,because the control lug 215 provided on one side of the reel shaftselection slider 101 compresses against the horizontal surface section214b of the cam portion 214, as shown in FIG. 14. On the other hand,since the control lug 228 provided on the other side of the reel shaftselection slider 101 compresses against the inclined surface section227a of the cam portion 227, the second lock lever 221 is rotated in thedirection indicated by arrow Q in FIG. 14, under the bias of the torsioncoil spring 226, so that the retention portion 223 is engaged with thesecond gear portion 205 of the second clutch gear 202.

If, in this state, the magnetic tape 7 is run at a constant velocity inreverse, the second clutch gear 202 has the first gear portion 204rotated with rotation of the reel shaft gear 95 and has the second gearportion 205 locked against rotation by the second lock lever 221, sothat a slip is generated between the first gear portion 204 and thesecond gear portion 205 to generate a pre-set load. Thus, when themagnetic tape 7 is taken up on the supply side tape reel 23, it is runwith a back tension and taken, up on the tape reel 6 in a trim windingstate on the tape reel 5 without producing slack during rewinding.

When taking up the magnetic tape 7 pulled out on the tape running routeinto the tape cassette 1 to start unloading, the reel shaft selectionslider 101 has been moved in the direction indicated by arrow X₂ in FIG.12, as shown in FIG. 13. Thus, the retention portion 213 of the firstlock lever 208 is not engaged with the second gear portion 205 of thefirst clutch gear 201, while the retention portion 223 of the secondlock lever 221 is engaged with the second gear portion 205 of the firstclutch gear 201. If, in this state, the driving motor 34 is run inrotation, the cam gear 36 of the movable guide block movement actuatingunit 151 is run in rotation via gear train 35, as shown in FIGS. 4 and5, so that the slider 39 is moved via rotation actuating member 37a. Ifthe slider 39 is moved, the limiter plate 55, having the cam opening 57engaged by the supporting pin 58 provided on the slider 39, is rotatedabout the pivot 53a as center. By rotation of the limiter plate 55, thelimiter plate 54, provided with the gear portion 54a meshing with thegear portion 55a provided on the limiter plate 55, is rotated in theopposite direction to the direction of rotation of the limiter plate 55,about the pivot 53a as the center of rotation. The first and secondmovable guide blocks 27, 28 are moved via the first to third connectionarms 51 to 53, under guidance by the movement guide grooves 32, 33, fromthe position corresponding to the loading end position of the magnetictape 7 laterally of the rotary magnetic head device 26 to the positionfacing the spacing 17 of the tape cassette 1 loaded on the cassetteloading unit 22, as shown in FIG. 4 and as shown in FIG. 5. The magnetictape 7 is taken up on the tape reel 5 by the capstan motor 25 being runin rotation to rotate the reel shaft driving gear 96 meshing with theclutch gear 99 via the driving power transmission unit 152 to causerotation of the reel shaft 23.

The rotary magnetic head device 26, used for the tape recorder, includesa tape guide drum 390 made up of a rotary drum 391 and a fixed drum 392,and a head driving motor 394 adapted for rotationally driving the rotarydrum 391, as shown in FIG. 16. The rotary drum 391 carries a rotarymagnetic head 26a, while the fixed drum 392 is arranged coaxially withand below the rotary drum 391. The rotary drum 391 and the fixed drum392 are in the form of cylinders of approximately the same diameter.

In the rotary magnetic head device 26, a supporting base block 393 ismounted on the base 21, on the upper surface of which the tape runningroute for the magnetic tape 7 is formed, or on the main body unit of thetape recorder, with a pre-set angle of inclination to the base 21. Thefixed drum 392 of the tape guide drum 390 and the head driving motor 394are mounted on the upper surface and on the lower surface of thesupporting base block 393, respectively. When the head driving motor 394is mounted on the supporting base block 393, the distal end of thedriving shaft 395 is passed through the fixed drum 392 so as to beprotruded on the upper surface of the supporting base block 393. Therotary drum 391 is mounted as-one on the distal end of the driving shaft395 protruded on the upper surface side of the supporting base block 393and is run in rotation along with the rotary magnetic head 26a byrotation of the head driving motor 394.

The rotary magnetic head device 26, thus mounted on the base 21 or onthe main body unit of the tape recorder with a tilt relative to the base21, is mounted in the main body unit so that the driving shaft 395 ofthe head driving motor 394 is inclined relative to the base 21, as shownin FIGS. 16 and 17.

The magnetic tape 7, pulled out from the tape cassette 1, is wound onthe outer periphery of the tape guide drum 390 over an angle of 160° asdescribed above. Since the tape guide drum 390 is arranged with a anglerelative to the magnetic tape 7 running on the tape running route, themagnetic tape 7 is wound spirally on the outer periphery of the tapeguide drum 390.

The rotary magnetic head 26a is mounted on the rotary drum 392 so thatits distal end having a magnetic gap is slightly protruded from theouter peripheral surface of the tape guide drum 390.

The rotary drum 392 is rotated as the magnetic tape 7 spirally woundabout the tape guide drum 390 and clinched between the capstan shaft 61and the pinch roll 62 is run at a constant velocity so that the magnetictape 7 is brought into relative sliding contact with the rotary magnetichead 26a for forming a recording track inclined relative to thelongitudinal direction of the magnetic tape 7 for recording informationsignals or reproducing information signals recorded on the recordingtrack.

Meanwhile, the magnetic tape 7 is pulled out from the tape cassette 1 soas to run parallel to the upper surface of the base 21 in order to bespirally wound on the outer peripheral surface of the tape guide drum90. Therefore, at least first and second inclined guide pins 31a, 31b,provided on the first and second movable guide blocks 27, 28 adapted forguiding the magnetic tape 7 running parallel to the base 21 so as to bewound spirally about the tape guide drum 90 arranged at an angle to thebase 21, are mounted at an angle to the base 21.

The specified structure of the first and second movable guide blocks 27,28 are hereinafter explained.

The first and second movable guide blocks 27, 28 are provided withmovable base blocks 399 carried by the distal ends of first connectionarms 51, 51 making up the movable guide block movement actuating unit151 and which are moved between a position towards the cassette loadingunit 22 and a position laterally of the rotary head device 26 underguidance by the first and second movement guide grooves 32, 33.

Each movable base block 399 has a tubular movement guide shaft 401 onits lower surface and is mounted on the base 21 by having the movementguide shafts 401 inserted in the first and second movement guide grooves32, 33. The movable base block 399 is moved between the position towardsthe cassette loading unit 22 and the position laterally of the rotaryhead device 26 under guidance by the first and second movement guidegrooves 32, 33.

The guide roll 29 is set on the movable base block 399 and includes aroll 397 rotatably inserted in a pivot 403 set on the movable base block399 so that its proximal end is passed through the movement guide shafts401. On this roll 397 is wound the magnetic tape 7. The proximal end ofthe pivot 403 is formed as-one with a lower flange 398a, while the upperend thereof carries an upper side flange 398b. The magnetic tape 7, runaround the roll 397, has upper and lower side edges guided by a lowerflange 398a and an upper side flange 398b for controlling the windingposition on the roll 397.

The movable base block 399 is supported on the base 21 in a mannersafeguarded against incidental extrication from the first and secondmovement guide grooves 32, 33 by an anti-extrication member 403a mountedon the tip of the proximal end thereof for securing the pivot 403inserted into the movement guide shafts 401 to the movement guide shafts401.

The guide roll 29 is mounted upright on the base 21 because the pivot403 supporting the roll 397 is supported at right angles to the movablebase block 399.

The first and second inclined guide pins 31a, 31b are mounted via a pinmounting portion 399a provided on the movable base block 399. The firstinclined guide pin 31a mounted on the movable base block 399 so that,when the first movement guide block 27 is moved to a position of loadingthe magnetic tape 7 positioned laterally of the rotary magnetic headdevice 26 on the tape running route, the first inclined guide pin 31a isinclined towards the guide roll 29 which is the direction of inclinationof the rotary magnetic head device 26. The second inclined guide pin 31bprovided on the second movement guide block 28 is mounted on the movablebase block 399 with a tilt so that, when the second movement guide block28 has moved the magnetic tape 7 positioned laterally of the rotarymagnetic head device 26 to the position of loading the tape on the taperunning route, the second inclined guide pin 31b is levelled downtowards the rotary magnetic head device 26, as shown in FIG. 16.Specifically, since the role of the second inclined guide pin 31bprovided on the second movement guide block 28 is to guide the magnetictape 7, running from the lower side towards the upper side of the tapeguide drum 390 at the exit side of the tape guide drum 390 in a reversedmanner as shown in FIG. 5 to a parallel path to the base 21, the secondinclined guide pin 31b is mounted with a tilt on the movable base block399 so as to level down towards the rotary magnetic head device 26.

For reducing the size of the tape recorder, it is necessary to reducethe separation between paired first and second movable guide blocks 27,28 to as small a value as possible. If the separation between the pairedfirst and second movable guide blocks 27, 28 is reduced, the separationfrom the rotary magnetic head device 26 is also reduced, so that, whenthe first and second movable guide blocks 27, 28 are moved towards therotary magnetic head device 26, there is a risk of collision of thesecond inclined guide pin 31b, tilted towards the rotary magnetic headdevice 26, against the tape guide drum 390, if the second inclined guidepin 31b is collided against the tape guide drum 390, not only can themagnetic tape 7 not be wound on the outer periphery of the tape guidedrum 390, but also the rotary magnetic head device 26 inclusive of thetape guide drum 390 or the magnetic tape 7 is likely to be destroyed.Therefore, the first and second movable guide blocks 27, 28 need to bemounted with a separation so as to be free of collision with the rotarymagnetic head device 26. However, if the separation between the firstand second movable guide blocks 27, 28 and the rotary magnetic headdevice 26 is increased, the tape recorder cannot be reduced in size.

The tape recorder according to the present invention is aimed atresolving the above-mentioned problem to reduce the size of the taperecorder further.

With the tape recorder according to the present invention, the magnetictape 7 can be wound over a pre-set angle on the tape guide drum 390, asthe collision of the second inclined guide pin 31b against the tapeguide drum 390 is controlled, despite the fact that the second movementguide block 28 having the second inclined guide pin 31b inclined towardsthe rotary magnetic head device 26 has a trajectory of contacting withthe tape guide drum 390 in the course of movement of the second movementguide block 28 towards the rotary magnetic head device 26.

The second movement guide block 28 having the second inclined guide pin31b inclined for levelling down towards the rotary magnetic head device26 is supported so that it can be tilted a pre-set angle relative to thebase 21 in a direction indicated by arrow Y₁ in FIG. 18 or in adirection indicated by arrow Y₂ in FIG. 19. That is, the second movementguide block 28 can be tilted relative to the base 21 by providing anallowance between the movement guide shafts 401 adapted for supportingthe second movement guide block 28 on the base 21 and the secondmovement guide groove 33 into which is inserted the movement guideshafts 401.

The rotary magnetic head device 26 is provided with a thrusting portion396 for clearing the second movement guide block 28 from the rotarymagnetic head device 26 when the second movement guide block 28 is movedto close to the rotary magnetic head device 26, with the second inclinedguide pin 31b colliding against the tape guide drum 390. This thrustingportion 396 is formed so that a portion of the supporting base block 93is protruded towards the movement trajectory of the second movementguide block 28, as shown in FIGS. 16 and 17.

Since the second movement guide block 28 is supported with a tiltrelative to the base 21, and the rotary magnetic head device 26 isprovided with the thrusting portion 396, the movable base block 399compresses against the thrusting portion 396 when the second movementguide block 28 is moved towards the rotary magnetic head device 26 andthe second inclined guide pin 31b collides against the tape guide drum390. When the movable base block 399 is moved from the positioncompressing against the thrusting portion 396 in a direction towards thelateral side of the rotary magnetic head device 26, the second inclinedguide pin 31b is inclined in a direction in which the second inclinedguide pin 31b is spaced apart from the tape guide drum 390 so that thesecond movement guide block 28 is moved in a state in which the secondinclined guide pin 31b is prevented from colliding against the tapeguide drum 390.

The second movement guide block 28, tilted by the thrusting portion 396,is further moved and released from the thrusting by the thrustingportion 396 so as to be tilted towards the rotary magnetic head device26. However, the second inclined guide pin 31b reaches a positionsufficiently spaced apart from the tape guide drum 390 and hence is notcontacted with the tape guide drum 390.

Similarly to the second movement guide block 28, the first movementguide block 27 is supported at an angle relative to the base 21, so thatit can be moved easily through the first inclined guide groove 32,having a curved mid portion, and hence the magnetic tape 7 can bereliably loaded/unloaded by the first and second movable guide blocks27, 28.

When reaching the tape loading complete position in which the magnetictape 7 is wound about the tape guide drum 390, the first and secondmovable guide blocks 27, 28, tiltably supported by the base 21, are setto a controlled tilt position by the movable base blocks 399, 399engaging in the positioning members 27a, 28a provided on the base 21.With the movable base blocks 399, 399, positioned in this manner, thefirst and second movable guide blocks 27, 28 can correctly guide therunning direction of the magnetic tape 7 by the guide roll 29 and theinclined guide pins 31a, 31b in order to take up the magnetic tape 7around the tape guide drum 390.

In the above-described embodiment, the thrusting portion 396 is providedon the supporting base block 393 for tilting the second movement guideblock 28 in a direction away from the rotary magnetic head device 26.Alternatively, the facing surfaces of the second movement guide groove33 may be formed with inclined surfaces 408, 409, as shown in FIG. 20.These inclined surfaces 408, 409 are provided ahead and at back of theposition of contact of the second inclined guide pin 31b with the, tapeguide drum 390 by movement of the second movement guide block 28 towardsthe rotary magnetic head device 26.

The inclined surfaces 408, 409 may also be provided only on one lateralside of the second movement guide groove 33.

In the tape recorder having the above-described rotary magnetic headdevice 26, the recording/reproducing unit for recording and/orreproducing information signals under controlling the running of themagnetic tape 7 and a running control mechanism for the magnetic tape 7are explained.

Referring to FIG. 21, the tape recorder according to the presentinvention includes a recoding signal processing unit 410 for convertinganalog audio signals into digital signals for generating recordingsignals, and a recording/reproducing unit 420 for recording signals fromthe recoding signal processing unit 410 on the magnetic tape 7 byhelical scan and for reproducing and outputting the signals recorded onthe magnetic tape 7. The tape recorder according to the presentinvention also includes a reproduced signal processing unit 430 forconverting the reproduced signals from the recording/reproducing unit420 into output analog signals, and a system controller 440 forcontrolling the recording/reproducing unit 420 and the playback signalprocessing unit 430.

Referring to FIG. 21, the recording signal processing unit 410 includesan amplifier 411 for amplifying analog audio signals, a Low-Pass Filter(LPF) 412 for removing high frequency components of the amplified audiosignals, an Analog/Digital (A/D) converter 413 for converting audiosignals into audio data, an error detection code appendage circuit 414for appending error correction codes and a modulator 415 for modulatingthe audio data in accordance with a modulation system suited forrecording on the magnetic tape.

The amplifier 411 amplifies the input analog audio signals withpre-emphasis, if need be, to route the resulting signals to the LPF 412.The LPF 412 is a so-called pre-amplifier for removing frequencycomponents not less than one-half the sampling frequency (such as 48kHz) to route the resulting signal to the A/D converter 413. The A/Dconverter converts analog audio signals to, for example, 16-bit audiodata.

The error detection code appendage circuit 414 interleaves audio dataand encodes the interleaved data by double reed-Solomon code to routethe resulting signals to the modulator 415, which then modulates theaudio data, having the appended error detection correction codes, usinge.g., 8-10 modulation system, and appends sub-codes and pilot signalsfor the Automatic Track Following (ATF) system to route the resultingrecording signals to the recording/reproducing unit 420.

For recording signals in the present tape recorder, the recording modeis selected in order to execute tape loading of winding the magnetictape 7 pulled out from the tape cassette 1 on the outer peripheralsurface of the tape guide drum 26 of the rotary magnetic head device ina M-shape for an angular extent of approximately 160° and of enablingthe running of the magnetic tape 7. By this tape loading, the pinch roll62 is pressed against the capstan shaft 61 to clinch the magnetic tape 7to run it at a constant speed in the forward direction from the supplyside tape reel 5 towards the take-up side tape reel 6. At this time, thehead driving motor 394 of the rotary magnetic head device 26 starts itsoperation to rotate the rotary drum 391 carrying the rotary magnetichead 26a.

The rotary magnetic head 26a is run in rotation at e.g., 2000 rpm. Thecapstan shaft 61 is run in rotation by the capstan motor 25 at an rpmcorresponding to the pre-set tape running speed of e.g., 8.15 m/s. Atthis time, the supply side reel shaft 23 is enabled to be rotated sothat the takeup side reel shaft 24 is run in rotation under the drivingpower of the capstan motor 25. The magnetic tape 7, pulled out from thesupply side tape reel 5 and wound about the tape guide drum 390, is runat a pre-set speed so as to be taken up on the take-up side tape reel 6of the tape cassette 1.

The tape recorder according to the present invention includes a rotaryspeed adjustment unit 429 for controlling the rotational speed of thecapstan motor 25 for controlling the rotational speeds of the takeupside and supply side reel shafts 23, 24, as shown in FIG. 22. Whenapplying braking to the supply side reel shaft 23, this rotary speedadjustment unit 429 controls the capstan motor 25 to control therotation of the takeup side reel shaft 24 to a rotational sped suited tothe winding diameter of the magnetic tape 7 wound on the takeup sidetape reel 6.

In this state, the rotary magnetic head device 26 causes the rotarymagnetic head 26a and the magnetic tape 7 to be slidingly contacted witheach other in order to record the signals supplied from the modulator415 on the magnetic tape 7 in accordance with the helical scan system.On the magnetic tape 7 is recorded an azimuth recording track on whichsignals are recorded in accordance with a pre-set format.

For reproducing the signals recorded on the magnetic tape 7, thereproducing mode is selected and, as in the above recording mode, themagnetic tape 7, pulled out from the tape cassette 1, is placedapproximately 160° on the outer peripheral surface of the tape guidedrum 26 in an M-shape by way of the loading. By this tape loading, thepinch roll 62 is pressed against the capstan shaft 61 to clinch and runthe magnetic tape 7 in the forward direction from the supply side tapereel 5 towards the takeup side tape reel 6 at a constant speed. At thistime, the head driving motor 394 of the rotary magnetic head device 26starts its operation to rotate the rotary drum 391 carrying the rotarymagnetic head 26a.

Although not shown, the tape recorder of the present invention has atrack servo system by which the rotational speed of the capstan motor 25is controlled based on ATF pilot signals recorded on the magnetic tape56.

When applying braking to the supply side reel shaft 23, the takeup sidereel shaft 25 is controlled by the rotary speed adjustment unit 429 to arotational speed suited to the winding diameter of the magnetic tape 7wound about the takeup side tape reel 6. The magnetic tape 7 is pulledout from the supply side tape reel 5 of the tape cassette 1 so as to bewound about the tape guide drum 390 of the rotary magnetic head 26 whichis then run at a speed perpetually scanning the azimuth recording trackbefore being rewound on the takeup side tape reel 6 of the tape cassette1.

By the rotary magnetic head 26a scanning the azimuth recording track ofthe magnetic tape 7, the signals recorded on the magnetic tape 7 arereproduced as playback signals which are sent to the playback signalprocessing unit 430. Referring to FIG. 21, the tape recorder accordingto the present invention includes a demodulator 431 for demodulatingplayback signals from the playback signal processing unit 430, an errorcorrection circuit 432 for correcting audio data from the demodulator431 for errors, a D/A converter 433 and an LPF 434 for convertingerror-corrected audio data into analog audio signals and a lineamplifier 35 for amplifying audio signals from the LPF 434.

The demodulator 431 is a counterpart of the modulator 415 of therecoding signal processing unit 410 and converts the playback signalssupplied from the recording/reproducing unit 420 into binary signalswhile simultaneously demodulating the resulting binary-valued signals byinverse 8-10 modulation to route the reproduced audio data to the errorcorrection circuit 432. The error correction circuit 432 corrects theaudio data for errors, using Reed-Solomon codes, while deinterleavingand routing the error-corrected speech data to the D/A converter 433.The D/A converter 433 and the LPF 434 convert the speech data intoanalog audio signals. The amplifier 435 amplifies audio signals withde-emphasis and routes the resulting signals to, for example, anamplifier of a stereo device for reproducing signals recorded on themagnetic tape 7.

The mechanism for controlling rotation of the capstan motor 25 forcontrolling the running speed of the magnetic tape 7 and the rotationalspeeds of the supply side reel shaft 23 and the take-up side reel shaft24 is explained.

The tape recorder according to the present invention includes sensors441, 442, 443 for detecting the rotational speeds of the supply sidereel shaft 23, capstan motor 25 and the take-up side reel shaft 24, asshown in FIG. 22. The sensors 441 to 443 are made up of, for example,Hall devices, which output FG signals to the system controller 440 asdetection signals of frequencies proportionate to the rotational speedsof the respective shafts depending on the rotation of the magneticmaterial mounted on the supply side reel shaft 23, capstan shaft 61 asdriving shaft of the capstan motor 25 and the take-up side reel shaft24.

The system controller 440 outputs a rotational speed control signalcontrolling the rotational speed of the capstan motor 25 based on thefrequency of the FG signal outputted by the sensors 441 to 443 to routethe control signals to the rotary speed adjustment unit 429. The rotaryspeed adjustment unit 429 controls the rotational speed of the capstanmotor 25 responsive to the rotational speed control signals outputted bythe system controller 440. The system controller 440 perpetually detectswhich position of the entire length of the magnetic tape 7 is beingscanned by the rotary magnetic head 26a, during running of the magnetictape 7, based on the FG signals detected by the sensors 441 to 443. Thesystem controller 440 calculates the winding diameter of the magnetictape 7 wound about the supply side tape reel 5 and the takeup side tapereel 6.

During the recording mode or the playback mode of running the magnetictape 7 in the forward direction, PWM signals of a pre-set wave crestvalue are supplied to the capstan motor 25 via rotary speed adjustmentunit 429, as shown in FIG. 23. The PWM signals, supplied to the capstanmotor 25, are controlled in duty based on the rotational speed controlsignal generated on the basis of the FG signals outputted by the sensors441 to 443. The rotary speed adjustment unit 429 routes the PWM signals,controlled on the basis of the rotational speed control signal, to thecapstan motor 25 to perform control to run the magnetic tape 7 at aconstant speed.

If the fast feed mode or the fast search mode is selected, the systemcontroller 440 sets the supply side tape reel 23 free in rotation, withthe magnetic tape 7 wound about the rotary magnetic head device 26. Thesystem controller 440 also performs controls so that the head drivingmotor 394 rotationally driving the rotary drum 391 is run at a pre-setrotational speed, and so that the pinch roll 62 is spaced apart from thecapstan shaft 61 to permit the magnetic tape 7 to run freely. The systemcontroller 440 also controls the rotary speed adjustment unit 429 sothat PWM signals having a wave crest values sufficiently higher thanthose during the recording mode or the reproducing mode will be suppliedto the capstan motor 25 in order to permit the capstan motor 25 to berotated at an elevated speed during the normal running direction, asshown in FIG. 23.

If the capstan motor 25 is rotated in the forward direction, the drivingpower transmission unit 152 is controlled to transmit the driving powerof the capstan motor 25 to the takeup side reel shaft 24 so that themagnetic tape 7 is run at an elevated speed from the supply side tapereel 5 to the takeup side tape reel 6.

If the high-speed search mode is selected, the recording track isscanned by the rotary magnetic head 26a slidingly contacted with themagnetic tape 7 running at an elevated speed for searching e.g., theleading end of the unit information signal corresponding to a musicalnumber recorded on the magnetic tape 7.

If the running of the magnetic tape, run at the elevated speed for thefast feed scanning mode or the high speed search mode, is halted, or theleading end address of the musical number being retrieved or thetrailing end of the magnetic tape 7 is detected, the system controller440 controls the rotary speed adjustment unit 429 so that the PWM signalof the wave crest value enabled at the minimum rpm of the capstan motor25 will be sent to the capstan motor 25, as shown in FIG. 23. The systemcontroller 440 then routes to the capstan motor 25 the control PWMsignal having the duty corresponding to the winding diameter of themagnetic tape 7 placed on the supply side tape reel 5 as detected by thesensors 441 to 443 in order to apply braking to the capstan motor 25.Specifically, the system controller 440 routes to the capstan motor 25via rotary speed adjustment unit 429 the control PWM signal of theperiod of 60 ms and the duty of 17% (that is 10 ms) corresponding to thewinding diameter of the magnetic tape 7, placed on the supply side tapereel 5, as shown in FIG. 23. This starts the braking to the capstanmotor 25. At this time, the system controller 440 monitors therotational speed of the capstan motor 25, based on the FG signalsupplied from the sensor 427. When the rotational speed of the capstanmotor 25 is below a pre-set threshold value, that is if the rotationalspeed of the capstan motor 25 falls below a pre-set value, the supply ofthe control PWM signals to the capstan motor 25 is halted or the PWMsignal corresponding to the minimum driving voltage of the capstan motor25 is supplied to prevent loose winding of the magnetic tape 7 to enabletape takeup.

The above-given values of the period and duty of the control PWM signalsare merely illustrative. These values are such values that the supplyside tape reel 5, rotating by inertia when the rotation of the takeupside tape reel 6 is stopped, also ceases its rotation. This enables fastfeed to be halted without producing the problem of loose winding of themagnetic tape 7 which occurred in the conventional rotary magnetic headtype tape recorder at the time of tape stop.

Meanwhile, if the end of the magnetic tape 7 is detected, the controlPWM signal with the duty of 100% is supplied until the halting of thecapstan motor 25. That is, if the trailing end of the magnetic tape 7 isdetected by tape end detection means not shown, there is no magnetictape 7 on the supply side tape reel 5, so that there occurs no problemof tape slack in the magnetic tape 7.

The tape end detection means optically detects leader tape end portionsprovided on the leading and trailing ends of the magnetic tape 7 todetect tape ends to send the results of detection to the systemcontroller 440.

The rewind mode for the magnetic tape 7 is basically the same as theabove-described fast feed mode.

If the rewind mode is selected, the system controller 440 is responsiveto the signals associated with this operating mode to set the takeupside reel shaft 24 free in rotation, with the magnetic tape 7 kept inthe wound state in the rotary magnetic head device 26. The systemcontroller 440 also performs control so that the head driving motor 394for rotationally driving the rotary drum 391 will be rotated at apre-set rotational speed. The system controller 440 also performscontrol so that the pinch roll 62 is separated from the capstan shaft 61to permit free running of the magnetic tape 7 and so that the drivingpower of the capstan motor 25 will be directly transmitted to the supplyside reel shaft 23. This enables the magnetic tape 7 to be run at aspeed higher than the ususal running seed for reproduction and taken upvia the rotary magnetic head device 26 on the supply side tape reel 5.

If the halting operation is performed during the rewind operation of themagnetic tape 7, the control PWM signal, having the duty correspondingto the winding diameter of the magnetic tape 7 wound on the takeup sidetape reel 6, calculated as described above, is sent from the systemcontroller 440 to the capstan motor 25. At this time, the rotary speedadjustment unit 429 is switched by the system controller 440 so that thecontrol PWM signal supplied to the capstan motor 25 is of a polaritysuch that the capstan motor 25 is rotated in the opposite direction tothe direction of rotation during the rewind mode.

The system controller 440 monitors the rotational speed of the capstanmotor 25, based on the FG signal from the sensor 427 and, when therotational speed of the capstan motor 25 is below a pre-set value, thesystem controller 440 halts the supply of the control PWM signal to thecapstan motor 25. This assures halting of the rewind mode without theproblem of producing loose winding of the magnetic tape on the tape reelwhich occurred in the conventional rotary magnetic head system taperecorder at the time of halting of tape running.

In the above-described embodiment, the capstan motor is used withoutemploying a dedicated driving motor for driving the supply side andtakeup side reel shafts. However, the present invention may be appliedto an embodiment in which the dedicated driving motors for driving thesupply and takeup side reel shafts. In this case, it is the drivingmotor for driving the reel shaft that is controlled.

Although the above-described embodiment is applied to the tape recorderhaving the rotary magnetic head device, the present invention can bewidely applied to recording and/or reproducing apparatus having therotary magnetic head device and employing a magnetic tape as a recordingmedium, such as a video tape recorder for recording and/or reproducingvideo signals, with equivalent merits.

Industrial Applicability

The above-described magnetic tape recording and/or reproducing apparatusaccording to the present invention has a switching mechanism having acounter gear which is positioned between the supply side reel gear andthe takeup side reel gear during the loading operation of the magnetictape by the tape loading mechanism. The counter gear of the switchingmechanism is selectively engaged with the supply side reel gear or thetakeup side reel gear after completion of loading of the magnetic tapein order to control the running direction of the magnetic tape. Thus,the running direction of the magnetic tape can be controlled only byswitching of the counter gear to enable prompt switching of the runningdirection of the magnetic tape.

Moreover, with the magnetic tape recording and/or reproducing apparatusaccording to the present invention, one of paired movement guides of atape pull-out mechanism movable between the position of pulling out themagnetic tape from the tape cassette loaded on the cassette loading unitand the position of winding the magnetic tape about the tape guide drumof the rotary magnetic head device is inclined in a direction away fromthe rotary magnetic head device. Thus, the movable guides can be movedcloser to the rotary magnetic head unit arranged with a tilt thusreducing the separation between the paired movable guides and the sizeof the device to enable protection of the magnetic tape and the rotarymagnetic head device.

Moreover, with the magnetic tape recording and/or reproducing accordingto the present invention, the control signal is supplied to enable thecapstan motor responsible for tape running to be rotated in reverse atthe time of decelerating or halting the magnetic tape from the state ofrunning at a constant velocity. Thus, the magnetic tape can be preventedfrom running by inertia to enable magnetic tape to be taken up withoutproducing tape slack.

What is claimed is:
 1. A recording and/or reproducing apparatus for amagnetic tape of a tape cassette, comprising:a supply side reel forreeling out the magnetic tape; a supply side reel gear for rotationallydriving the supply side reel; a takeup side reel for taking up themagnetic tape; a takeup side reel gear for rotationally driving thetakeup side reel; a tape guide drum wound with the magnetic tape pulledout from the tape cassette; a tape loading mechanism for pulling out themagnetic tape from the tape cassette and placing the magnetic tape onthe tape guide drum by way of a tape loading operation and forseparating the magnetic tape from the tape guide drum and housing themagnetic tape in the tape cassette by way of a tape unloading operation;and a switching mechanism for switching a running direction of themagnetic tape pulled out from the tape cassette by the tape loadingmechanism, wherein the switching mechanism includes a counter gearmovable between a position in which the counter gear selectively mesheswith one of the supply side reel gear and the takeup side reel gear forselectively driving one of the supply side reel gear and the takeup sidereel gear and a position in which the counter gear is positioned betweenthe supply side reel gear and the takeup side reel gear and is out ofcontact with both the supply side reel gear and the takeup side reelgear, and wherein the counter gear is positioned during the tape loadingoperation by the tape loading mechanism to be out of contact with boththe supply side reel gear and the takeup side reel gear.
 2. Therecording and/or reproducing apparatus as recited in claim 1, whereinthe counter gear is engaged with one of the supply side reel gear andthe takeup side reel gear during the tape unloading operation by thetape loading mechanism.
 3. The recording and/or reproducing apparatus asrecited in claim 2, wherein the counter gear includes a clutchmechanism.
 4. The recording and/or reproducing apparatus as recited inclaim 2, wherein upon completion of the tape unloading operation by thetape loading mechanism, the counter gear is moved to a positionintermediate between the supply side reel gear and the takeup side reelgear and is out of contact with both the supply side reel gear and thetakeup side reel gear.
 5. The recording and/or reproducing apparatus asrecited in claim 2, wherein the tape loading mechanism includes a pairof movement guides movable between a position for pulling out themagnetic tape from the tape cassette and a position of winding themagnetic tape pulled out from the tape cassette around the tape guidedrum, and a movement guide mechanism for moving the pair of movementguides, the movement guide mechanism of the tape loading mechanism beingdriven by a driving mechanism.
 6. The recording and/or reproducingapparatus as recited in claim 5, wherein the movement guide mechanismincludes a cam gear having a cam portion for driving the movement guidemechanism and a slider moved by the cam gear for driving the movementguide mechanism.
 7. The recording and/or reproducing apparatus asrecited in claim 5, further comprising:an operating mechanism fortilting one of the pair of movement guides in a direction away from thetape guide drum when the pair of movement guides are moved to a positionproximate to the tape guide drum.
 8. The recording and/or reproducingapparatus as recited in claim 7, further comprising:supporting means forrotatably supporting the tape guide drum, wherein the operatingmechanism is provided on the supporting means.
 9. The recording and/orreproducing apparatus as recited in claim 8, whereinthe operatingmechanism is a lug provided on the supporting means and is abuttedagainst the one of the pair of movement guides in order to tilt the oneof the pair of movement guides.
 10. The recording and/or reproducingapparatus as recited in claim 5, further comprising:a switchingmechanism moved by the driving mechanism for selectively engaging thecounter gear with one of the supply side reel gear and the takeup sidereel gear.
 11. The recording and/or reproducing apparatus as recited inclaim 10, whereinthe driving mechanism includes a cam gear having a camportion for driving the switching mechanism and a slider moved by thecam gear for driving the switching mechanism.